1. Technical Field
The present invention relates to a thermal electron emission backlight device and, more particularly, to a back light device that emits white light by exciting a phosphor layer using thermal electrons.
2. Related Art
A backlight device which emits white light is installed on a rear surface of a liquid crystal display (LCD). A plasma type cold cathode electrode tube has been mainly used as the backlight. However, the cold cathode cold cathode electrode tube is not environmentally friendly since the cold cathode electrode tube uses mercury. In addition, it is becoming expensive since the structure is more complicated as it is bigger by using a light guide plate. In this regard, a mercury-free and flat panel type backlight is required. One exemplary backlight is a backlight which employs carbon nanotubes (CNTs).
A triode structure field emission device, as disclosed in U.S. Pat. No. 5,760,858, can solve the above problem, but the manufacturing process of the backlight is as complicated as the manufacturing process of a field emission display (FED). That is, the backlight is manufactured by a semiconductor manufacturing process, including deposition of a plurality of thin films and photolithography, thereby having a high manufacturing cost and a low yield when compared to the manufacturing of an LCD panel having a simple structure.